module

Imports System.Data.OleDb
Public Class Form1
    Dim Conn As OleDbConnection
    Dim cmd As OleDbCommand
    Dim da As OleDbDataAdapter
    Dim ds As New DataSet
    Dim dr As OleDbDataReader
    Dim LokasiDB As String
    Sub Koneksi()
        LokasiDB = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=dbjnm.accdb"
        Conn = New OleDbConnection(LokasiDB)
        If Conn.State = ConnectionState.Closed Then Conn.Open()
    End Sub
    Sub isiCombo()
        cmd = New OleDbCommand("Select namaBarang from Barang", Conn)
        dr = cmd.ExecuteReader
        Do While dr.Read
            ComboBox1.Items.Add(dr.Item(0))
        Loop
    End Sub
    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        ComboBox1.DropDownStyle = System.Windows.Forms.ComboBoxStyle.DropDown
        ComboBox1.AutoCompleteMode = AutoCompleteMode.SuggestAppend
        ComboBox1.AutoCompleteSource = AutoCompleteSource.ListItems
        Koneksi()
        da = New OleDbDataAdapter("Select * from barang", Conn)
        ds = New DataSet
        ds.Clear()
        da.Fill(ds, "Barang")
        DataGridView1.DataSource = (ds.Tables("Barang"))
        isiCombo()
    End Sub

    Private Sub ComboBox1_GotFocus(sender As Object, e As EventArgs) Handles ComboBox1.GotFocus
        ComboBox1.DroppedDown = True
    End Sub
End Class